Improvement in artificial legs



y* UNITED STATES NPATENT OFFICE.

IMPROVEMENT IN ARTIFICIAL LEGS.

Specification forming part ot' Letters Patent No. 39,599, dated August 18, 1863.

To all whom, it may concern:

Be it known that I, THOMAS UnEN,'of the city and county of San Francisco, and State of California, have invented a new and Improved Artificial Leg; and I do hereby declare that the followingis a full, clear, and exact description of the same, reference being had to the annexed drawings,inaking a part of this speciiication, in which# Y Figure l represents an artificial, leg and thigh with the various attachments. Fig. 2 represents the leg and thigh witha portion of the lower limb removed, so as to show the internal arrangement. Fig. 3 represents the sole of the foot. Figs. 4, 5, and 6 represent portions ot' the joints or hinges. Fig. 7 represents an artificial leg to be used when amputation has taken place below the knee. Fig. 8 represents an enlarged view of the foot and leg represented in Fig. 2.

Y A is a leather socket to t upon the thigh. Thelowtr end of this socket terminates in a block of wood of hcmispherical form.

B is the leg attached to the socket or thigh A by the Strap-hinges h. The lower extremity of the leg, as shown at b, is convex in .form and iits into a corresponding cavity in the foot C.

lC is the foot, and is formed in three partsviz., the main foot, a portion, m, corresponding to the metatarsal bones, and the toes t-each part being hinged to its corresponding part by joints formed of a convex surface working upon a corresponding concave surface, hinged horizontally in the center, so as to give an upward and downward motion similar to that of the natural joints.

m represents the inetatarsal joint, and t thetoes.

s s are spiral springs connecting the lower part of the metatarsal joint m with the Jfoot G. s s are also spiral springs connecting the upper part of the toejoint with the foot.

a a a are cords representing tendons, attached at their lower ends to the upper side of the toes t, and at their upper ends to a strap, a', which stra p passes upward over a pulley, p, in the leg, thence downward round the pulley p, attached to the heel of the foot, thence upward, and is fastened to the lower and hinder part ofthe leg at d. A cord or strap, e, is attached to the under side of the toes t, passes thence round the pulley pf, thence upward to the front and lower part of the leg, to which it is attached at m.

r is a cord or strap attached at its lower end to the instep, thence passing upward over the double pulley p, thence downward to the heelI where it is fastened. The foot `is attached to the leg. by a pinv at b, which passes through a staple in the center of the joint. The convex part of this joint is a little thicker in its center, so as to allow of a very slight lateral motion, and between the two surfaces of the joint a piece ot' leather is placed, so as to prevent any rattling.

s" is a spiral spring attached at its upper end to the same pin which holds the pulley p, and at its lower end to theinstep. s is also a spiral spring, attached at its lower end to the pin of the pulley p and terminating at its up- A per end with a strap,z', which strap passes over the knee and across the upper surface of the wooden block forming the knee, and is t'astened by a screw at q, or any other convenient point. Attached to the upper and front part of the leg is a double cord or strap, n, the two parts of which pass thence to the knee-cap k,

to which they are fastened; thence they pass l one on each side through the thigh over pulleys o, andare attached to the upper and hinder part of the leg, as shown at o.

x is a strap or cord, known as-the tendo Achilles,77 for raising the heel when the wearer is in a sitting posture.

rlhe hinges h are of a peculiar construction, one portion being countersunk, forming a sort of a cup, as shown in Fig. 5. The other part of the hinge has a corresponding shoulder, as shown at W in Fig. 6, which represents an end view. The parts are held together by screws or rivets. All the wear is upon the outer edge ot' the shoulder W, and upon the inside face of the cup, entirely relieving the screw or rivet both from strain and wear.

E is a belt, to be worn above lthe hips, to which the socket or thigh A is attached by straps.

To prevent the weight of the leg dragging too much upon the hips, a jacket, F, is used, to which the belt E is bnttoned', or otherwise fastened. Y

Another and valuable part of my invention is the crutch G, formed in three parts, made of steel or other suitable material. The lower part, l[,is hinged to the upper partof the socket or thigh A by the shoulder and socket hinge hereinbefore described, the projection or catch I preventing the crutch from fallin gbackward. A screw-thread is cut in the upper end of the part H, also a corresponding thread upon the lower end of G for the purpose ot'len gthenin g or shortening the crutch. The head L 'ot' the crutch turns on a swivel, to accommodate itself to the movement of the shoulders.

R is a belt, for the purpose of keeping the upper part ofthe crutch in place.

The leg or lowerlimb, as shown in Fig. 7, is similar to what has been above described, except that the spring 6', the cord or strap X,

.the knee-block, and straps or cords connected therewith are dispensed with. j

Operation: The socket A is fitted to the stump of the thigh, and is attached to the belt E, which may he used either with or without 'the jacket F and crutch G, or either of them, theV belt It being used only when the crutch is used. j When walking, the pressure upon the heel throws the instep down, drawing upon the cord e, bringing the toes tirmly down upon the ground. In liftingthe foot to step forward, the spring s draws up the instep, and the springs s s raise the toes, so that in stepping they clearl the ground, allowing' the 'wearer `in walking upon level ground or up stairs to do so without the usual awkward lateral fswin gingv motion lso common in using artilicial legs. yThe cord or strap r is useful in giving steadiness to the ankle-joint. The cords ca a a and cord, or strap a are useful in case the Vsprings s s should give way. They also, when covered, contribute to the symmetry of the foot, representing the natural tendons. When the knee is bent, as in the actI ot' sitting, the strapz' is drawn taut, the spring 6 is dis.

tended, the cord or tendo Achilles raises the heel, and the toes are brought firmly to the ground, as in the act of walking. When the wearer is in a sitting posture, by bending the knee the cords u draw the knee pan 7c hard against the strap i in the manner of a brake, holding the joint in whatever position the wearer desires.

l The cords n are useful in keeping the kneejoint firm. All the straps and cords can be shortened whenever necessary.

The leg, when nished, should be covered with leather or other suitable material.

I claiml. In combination with the toe and metatarsal joints, the cord e and springs s and s', for raising and lowering the toes and nietatars'al joint, substantially as herein described. l 2. The cords a and strap or cord a', in combination with the pulleys p and p', substantially in the manner and for the purpose set forth. y

3. ln combination with pivoted foot C, the strap r, passing over pulley p, for the purpose of giving steadiness to the ankle-joint, substantially as herein described.

4. rIhe knee-pan K, in combination with the cords n and pulleys o, for the purpose of retaining the leg in any desired positionwhile in a sitting posture, substantially in the manner herein described.

5. In combination with the tendo Achilles strap X, the strap i, and spring 8', substantially in the manner and for the purpose herein set forth.

Y THOMAS UREN. Witnesses GHAsAR. BOND, O'rIs V. SAwYnR.V 

